Abstract

Heterodyne and homodyne optical communication receivers are now being extensively investigated.¹ One difficulty to overcome in such receivers is their sensitivity to polarization mismatch between signal and local oscillator (LO) lights. To prevent this effect various countermeasures against polarization fluctuations have been reported²: (1) use of a polarization-maintaining fiber in the signal lightguide; (2) use of a polarization diversity receiver; and (3) use of state-of-polarization (SOP) control devices. In a SOP device, the most important characteristic to be achieved is the continuity, that is, no need for resetting any type of SOP change in the incoming signal.

© 1988 Optical Society of America